1. Field of the Invention
The present invention relates to scroll sensors.
2. Background Art
A scroll sensor is useful for human input to an electronic device for purposes of menu selection, parameter control, etc. A scroll sensor is typically planar in the shape of a strip or a ring, and is typically built in the front face of an electronic device. A user activates a scroll sensor by touching or sliding on the sensor surface with a finger or an implement such as a stylus. The scrolling action may be linear, rotational, or along a more complex path.
Electronic devices that benefit from the utility of scroll sensors include cell phones, personal media players, personal digital assistants, portable gaming devices, cameras, remote controls, etc. Such electronic devices typically have a display with a graphical user interface (GUI) that may give feedback during scrolling actions. For example, changing the volume on a music player might be indicated on a GUI by a moving bar whose length is proportional to volume.
An example of a portable electronic device with a linear strip scroll sensor is the iRiver H10 mp3 player. Touching the strip scroll sensor and moving, or touching the strip scroll sensor at one end and holding, accomplishes various actions such as song selection, volume control, etc.
An example of a portable electronic device with a rotary ring scroll sensor is the Apple iPod. Touching the ring scroll sensor and scrolling around accomplishes various actions such as changing the volume, where the size of the change is proportional to the angular travel of the touch.
Portable electronic devices are trending toward increased functionality without a corresponding increase in physical size. The increased functionality is accompanied by a requirement for increased user input and interaction. There is therefore a demand for touch input devices such as mouse pointing sensors, strip scroll sensors, and ring scroll sensors which can be used in electronic devices.
A scroll sensor can be used for controlling a single parameter at a time, for example, the audio volume on an mp3 player. Subsequently, the same scroll sensor can be used for a second function such as scrolling through song lists. However, the scroll sensor cannot perform both functions at once. Switching between the two functions requires a function selection step such as context-sensitive switching or a button to actively switch which of the functions the scroll sensor will perform.
If multiple functions are to be simultaneously available without the provision of a function selection step, then multiple scroll sensors could be provided. This reduces the number of function selection steps and provides a more intuitive control. However, in order to enable smooth motions from one scroll sensor to the other scroll sensor it is desirable that the multiple scroll sensors be touching or even intersecting. Furthermore, to maintain pleasing aesthetics it is desirable that the multiple scroll sensors appear to be a single scroll sensor. Thus, what is needed is a touch input device having interleaved scroll sensors.